Add cpt codes to surgery query

[JackWilb]

Closes #188

Adds the logic to return all cleaned cpt code names from a surgery query. For example:

{
	"result": [
		{
			...
			"cpt": [
				"Thoracic Aorta Aneurysm Procedure",
				"CABG",
				"ECMO"
			]
		}
	]
}

A current by-product of this fix is that the visit number is now also returned as "hospital visit number" in the JSON. I guess that's not a huge issue, but we should probably not display that in the UI.

[haihan-lin]

also added front end code to process the CPT codes.